English
For matrices M and N, the mulVecLin of the product equals the composition of mulVecLin with mulVecLin.
Русский
Для матриц M и N выполняется: mulVecLin(M N) = (mulVecLin M) ∘ (mulVecLin N).
LaTeX
$$Matrix.mulVecLin (M * N) = (Matrix.mulVecLin M).comp (Matrix.mulVecLin N)$$
Lean4
@[simp]
theorem mulVecLin_mul [Fintype m] (M : Matrix l m R) (N : Matrix m n R) :
Matrix.mulVecLin (M * N) = (Matrix.mulVecLin M).comp (Matrix.mulVecLin N) :=
LinearMap.ext fun _ ↦ (mulVec_mulVec _ _ _).symm